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Drug Class: Commonly Known As: Category:
Analgesic Opioid Adult

Opioids - Side Effects, Precautions, and Contraindications

What side effects can Opioids cause?

Prescription opioids carry serious risks of addiction and overdose, especially with prolonged use. An opioid overdose can cause life threatening breathing difficulties often marked by slowed breathing, and can cause sudden death.

The use of prescription opioids can have a number of side effects as well, even when taken as directed. Only take your medicine as directed by your doctor carefully, if you have concerns please consult your doctor.

Common side effects which may occur with opioids include but are not limited to:

GastrointestinalConstipation, gastric discomfort, dry mouth, nausea and vomiting
NeurologicalDizziness, drowsiness
DermatologicalItch, rash
EyeBlurred vision

urinary retention

Some side effects such as nausea, vomiting and constipation may improve as you use the drug but other side effects may be prolonged. Your doctor may prescribe anti-sickness drugs (for nausea and vomiting) as well as laxatives (for constipation) to be used concurrently with your drug in order to alleviate its associated side effects.

If you find you are sleepy / drowsy or cannot concentration while taking the drug, do not drive or operate machinery. This is particularly a concern if the dose of the drug has recently been changed.

Opioids can cause serious life-threatening respiratory depression which can occur at any time during opioid use, and at any dose. Furthermore some individuals may be allergic to opioids. A person experiencing any of the following: significant confusion or severe drowsiness, significant difficulty waking or not being arousable, slowed breathing or not breathing, passing out or having a seizures, inability to urinate, swelling of the lips, face, tongue and throat; refer to a doctor as a matter of emergency (Call 995).

If you take the drug regularly for several days or more, your body may become accustomed to the drug. As a result you may develop effects of the drug upon sudden withdrawal. These may include sweating, gastrointestinal cramps, diarrhoea and muscle ache. If these occur, consult your doctor.

Furthermore the pain reducing effect as well as some side effects, may gradually decrease with regular use. If you find the effectiveness of the drug has decreased, or otherwise develop any unusual side effects, consult your doctor.

Before taking Opioids , what precautions must I follow?

Do check with your doctor or pharmacist before taking opioids if you:

- have any drug allergy, particularly with respect to pain killers.

-have any pre-existing medical condition including but not limited to : a history of seizures, altered / impaired liver or kidney  function, low blood pressure, irregular heart rhythm, any respiratory conditions (e.g. asthma, chronic obstructive pulmonary disease (COPD), chronic constipation or difficulty passing urine, alcoholism or a history of illicit drug use.

-are taking any medicine, including herbal remedies, traditional Chinese medicines or over the counter medicines.

What food or medicine must I avoid when I take Opioids ?

Opioids may increase the effects of drowsiness or other side effects caused by other drugs. This includes but is not limited to sleeping tablets, anti-anxiety tablets (including benzodiazepines such as diazepam, lorazepam and clonazepam), certain drugs for depression and psychiatric conditions, some antihistamines / allergy tablets, alcohol as well as other opioids and pain medication (including gabapentin and pregabalin). Inform your doctor if you are taking any other medication including herbal and over the counter medicines before using opioids.

Avoid alcohol if you are taking any opioids, as it will increase the risk of side effects.

Do not take over the counter medicines without first consultant your pharmacist / doctor 

Opioids - Additional Information

​Check with your doctor or pharmacist if you are pregnant, intend to get pregnant or are breast-feeding.  


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